I started MVP Lesson 1.6 today. I began with a notice/wonder of the context:
A key question I had going in was whether to make sure kids had thought about the total amount of candy in the machine (15 lbs * 180 candies/lbs) BEFORE releasing them to group work. I decided to opt not to do that, because we’ve had some long lesson launches recently and I wanted to get kids working in their groups as quickly as I reasonably could.
Three of my four classes had a student notice that there are 2,700 candies total, so in those classes we talked about why that was true. One class didn’t have anyone notice or wonder about the total amount of candy, so they went into their groups without having discussed that. This period made a lot of tables showing # of candies as a function of pounds.
Even the other classes that had discussed the total candy in the machine during the lesson launch struggled to note during group work that the question was asking them to represent the number of candies IN the machine (not the amount of candy coming out). I saw a lot of tables showing the sequence 7, 14, 21, …
In fact, in all of my classes, I only had one group find 2,700–7=2,693. When I asked them why they had subtracted and what the 2,693 represented, they freaked out and erased it and decided to multiply instead of subtracting. I saw a lot of work that seemed like kids were just doing mathematical operations without slowing down to think about WHY they were choosing WHICH operation and what the numbers MEANT.
The focus of this lesson is comparing increasing and decreasing arithmetic sequences. Thus, tomorrow’s Warm Up is designed to prime them to make a decreasing arithmetic sequence.